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991.
992.
目的 研究亚慢性染铝对断乳大鼠学习记忆和海马细胞内Ca2+及磷脂酶C(phospholipase C,PLC)、N-甲基-D-天冬氨酸受体α(NMDARα)表达的影响,以探讨铝损伤发育中大鼠学习记忆的可能机制.方法 刚断乳Wistar大鼠40只,随机分为4组:对照组、低剂量组(饮用含0.2%AlCl3的蒸馏水溶液)、中剂量组(饮用含0.4%AlCl3的蒸馏水溶液)、高剂量组(饮用含0.6%AlCl3的蒸馏水溶液),每组10只.通过饮水亚慢性连续染毒90 d,跳台试验检测仔鼠学习记忆能力,荧光分光光度计法测定细胞内Ca2+浓度,免疫印迹(Western blot)法测定PLC、NMDARα的表达.结果 随着染铝剂量的增加,大鼠跳台试验的潜伏期明显缩短,低、中、高剂量组分别为(232.20±57.45)、(35.00±9.37)、(16.10±5.57)s,而错误次数明显增加,低、中、高剂量组分别为(1.10±0.74)、(2.20±0.92)、(3.40±1.51)次,与对照组[分别为(300.00±0.00)s、(0.00±0.00)次]比较,差异均有统计学意义(P<0.05);而海马细胞内[Ca2+]i浓度明显下降,差异亦有统计学意义(P<0.05);低、中、高剂量铝暴露组PLC、NMDARα的表达水平分别为0.30±0.06、0.18±0.04、0.16±0.03,0.38±0.03、0.32±0.02、0.25±0.02,较对照组(分别为0.47±0.07、0.48±0.04)明显降低,差异均有统计学意义(P<0.01).结论 亚慢性铝暴露可以引起发育中学习记忆能力的损害,抑制NMDARα及PLC的表达,降低海马细胞内Ca2+水平,推测Ca2+信号系统的紊乱可能是铝损害学习记忆能力的机制之一. 相似文献
993.
目的 探讨腹腔镜下肝门血流阻断在肝切除术(LH)的解剖基础及手术路径。 方法 解剖尸体肝脏,分离血流阻断所涉及各肝门结构,观察在二维平面中毗邻,测量在肝外长度及夹角;观察LH视频中肝门结构,总结镜下的位置及特征。 结果 肝动脉平面低于肝管(90%),肝门静脉分叉位置固定于后方;肝左和肝中静脉在肝外大多共干(90%),肝右静脉与共干间存在间隙,与肝后下腔静脉(IVC)前方相通;肝短静脉位于IVC两侧,有(7±3)支;IVC韧带在尸体中易忽略,活体中较明显,为包绕IVC的膜性结构,厚度个体差异大;各结构在肝外长度及夹角为肝门血流阻断提供足够空间;镜下各结构位置及特征与实体比较有特殊性。 结论 LH中应用肝门血流阻断有解剖依据及路径遵循。 相似文献
994.
Quinan BR de Brito Magalhães CL Novaes RF Dos Santos JR Kroon EG Bonjardim CA Ferreira PC 《Virus genes》2008,36(3):435-437
The Tahyna virus (TAHV) is an important human pathogen in the Bunyaviridae family. To date, only the S and M segments of this virus have been sequenced, but the sequence of the L segment hasn’t been
established yet. In this study, we sequenced 963 nucleotides of the L segment of TAHV, comprising pre-motif A and motif A
in region 3 of the RNA polymerase gene.
The nucleotide sequence data reported in this paper was submitted to the GenBank nucleotide sequence database: EU185046. 相似文献
995.
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997.
We investigated the perceptions of and adherence to medication and physical activity guidelines in 174 adults with Marfan syndrome. Over 80% of those prescribed beta- and Ca2+-channel blockade reportedly adhere well to their medication regimen. The presence of cardiovascular symptoms and fatigue were positively correlated with the medication use. Medication-takers reported that they are psychologically receptive to the use of medication for prophylactic treatment of their cardiovascular problems. However, all do not view their medication as essential for their health. Duration of the medication regimen, type of medication, and perception of controllability of the condition were each independently associated with respondents' perceptions of the necessity of taking beta- or Ca2+-channel blockers. Over 80% of the respondents reported that they choose their physical activities with their diagnosis in mind. Modifying exercise activities was significantly correlated with an increased perception of Marfan syndrome as having negative consequences on the respondents' lives. Genetic counseling should address beliefs about medication use and physical activity restrictions, as perceptions of these health behaviors may have significant impact on how adults with Marfan syndrome adhere to these recommendations and cope with their condition. 相似文献
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1000.
Mila Leite de Moraes Maia Maria Amália Gonzaga Ribeiro Luiz Guilherme Martins Maia Juliana Stuginski-Barbosa Yuri Martins Costa André Luís Porporatti Paulo César Rodrigues Conti Leonardo Rigoldi Bonjardim 《Lasers in medical science》2014,29(1):29-35
This study investigated the effect of low-level laser therapy (LLLT) on the masticatory performance (MP), pressure pain threshold (PPT), and pain intensity in patients with myofascial pain. Twenty-one subjects, with myofascial pain according to Research Diagnostic Criteria/temporomandibular dysfunction, were divided into laser group (n?=?12) and placebo group (n?=?9) to receive laser therapy (active or placebo) two times per week for 4 weeks. The measured variables were: (1) MP by analysis of the geometric mean diameter (GMD) of the chewed particles using Optocal test material, (2) PPT by a pressure algometer, and (3) pain intensity by the visual analog scale (VAS). Measurements of MP and PPT were obtained at three time points: baseline, at the end of treatment with low-level laser and 30 days after (follow-up). VAS was measured at the same times as above and weekly throughout the laser therapy. The Friedman test was used at a significance level of 5 % for data analysis. The study was approved by the Ethics Committee of the Federal University of Sergipe (CAAE: 0025.0.107.000-10). A reduction in the GMD of crushed particles (p?<?0.01) and an increase in PPT (p?<?0.05) were seen only in the laser group when comparing the baseline and end-of-treatment values. Both groups showed a decrease in pain intensity at the end of treatment. LLLT promoted an improvement in MP and PPT of the masticatory muscles. 相似文献